A longtime friend of the man who allegedly killed his girlfriend and then stabbed himself reacts outside the apartment building where the grisly crime occurred. Photo: Theodore Parisienne

Police at the scene where a stabbed woman ran out of her apartment and collapsed in the street. She later died at Lutheran Hospital. (Theodore Parisienne)

Cops formally charged the man who fatally knifed his girlfriend, then turned the knife on himself April 6 around 10:30 a.m. on 51 Street near third Avenue, cops said.

Alex Santiago,44, shortly regained consciousness for a bedside arraignment where he was sedated in a coma, cops said.

He was charged with murdering Tara Bearsall, 31, who was pronounced dead at Lutheran Hospital after she ran into the street and collapsed trying to get away from Santiago during the scuffle, cops said.

In December of 2012, he was charged with unlawful imprisonment for holding Beardsall, 31, in the apartment and threatened her with a knife, the sources said. The couple had a history of domestic violence at their Brooklyn home, the sources said.